I use DeoVR in Oculus GO.
Oculus GO is a piece of shit. It has low output volume, and no plugins to boost volume overall. If I turn it up to 100% volume, I am stuck with that. I cannot go any higher.
Most studios are fine. E.g. I would never download a WankzVR scene and have to put the volume on 100%. Even 70% is fine with their videos.
However, SLR Originals videos are frequently too low in volume. I can barely hear things, even on 100%.
I opened some of the SLR videos in Audition and looked at the wave forms. It was hit and miss. Sometimes you mastered the audio, other times apparently not. I am sorry I don't have screenshots -- these things take up a lot of time and I can't be bothered. It would also involve downloading all the videos again, since my hard drive died, and I definitely can't be bothered with that.
The latest video however is a good example of low volume: https://www.sexlikereal.com/scenes/naughty-dorm-party-dope-arcade-21443
I used to do sound engineering and the first thing we would do to bring an audio track up to an acceptable volume level is to use the Normalize function. This does not use compression, but simply raises the volume of the whole sound wave so that the peaks are output at 0dB, which is the highest level for any device. People's volume controls will still work, so 70% volume will play the peaks at 70% of the capacity of the output of the device.
From what I saw, on your "unmastered" audio, you had volume peaks at -9dB, which is simply too low for most portable devices (and I'm not exactly going to blast porn on my big speakers now, am I?).
If, after Normalizing, volume is still too low, you would then look at Hard Limiting, which uses compression to bring more audio up closer to 0dB.
Sorry if I am "teaching my grandmother to suck eggs" here, but the volume is too low, FACT, and it needs to be looked at.
Thanks. π